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1.
Front Oncol ; 11: 645328, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912459

RESUMO

PURPOSE: How modern cardiac sparing techniques and beam delivery systems using advanced x-ray and proton beam therapy (PBT) can reduce incidental radiation exposure doses to cardiac and pulmonary organs individually or in any combination is poorly investigated. METHODS: Among 15 patients with left-sided breast cancer, partial wide tangential 3D-conformal radiotherapy (3DCRT) delivered in conventional fractionation (CF) or hypofractionated (HF) schedules; PBT delivered in a CF schedule; and volumetric modulated arc therapy (VMAT) delivered in an HF schedule, each under continuous positive airway pressure (CPAP) and free-breathing (FB) conditions, were examined. Target volume coverage and doses to organs-at-risk (OARs) were calculated for each technique. Outcomes were compared with one-way analysis of variance and the Bonferroni test, with p-values <0.05 considered significant. RESULTS: Target volume coverage was within acceptable levels in all interventions, except for the internal mammary lymph node D95 (99% in PBT, 90% in VMAT-CPAP, 84% in VMAT-FB, and 74% in 3DCRT). The mean heart dose (MHD) was the lowest in PBT (<1 Gy) and VMAT-CPAP (2.2 Gy) and the highest in 3DCRT with CF/FB (7.8 Gy), respectively. The mean lung dose (MLD) was the highest in 3DCRT-CF-FB (20 Gy) and the lowest in both VMAT-HF-CPAP and PBT (approximately 5-6 Gy). VMAT-HF-CPAP and PBT delivered a comparable maximum dose to the left ascending artery (7.2 and 6.13 Gy, respectively). CONCLUSIONS: Both proton and VMAT in combination with CPAP can minimize the radiation exposure to heart and lung with optimal target coverage in regional RT for left-sided breast cancer. The clinical relevance of these differences is yet to be elucidated. Continued efforts are needed to minimize radiation exposures during RT treatment to maximize its therapeutic index.

2.
Med Phys ; 47(8): 3286-3296, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32356335

RESUMO

PURPOSE: To present a fully automated treatment planning process for proton therapy including beam angle selection using a novel Bayesian optimization approach and previously developed constrained hierarchical fluence optimization method. METHODS: We adapted our in-house automated intensity modulated radiation therapy (IMRT) treatment planning system, which is based on constrained hierarchical optimization and referred to as ECHO (expedited constrained hierarchical optimization), for proton therapy. To couple this to beam angle selection, we propose using a novel Bayesian approach. By integrating ECHO with this Bayesian beam selection approach, we obtain a fully automated treatment planning framework including beam angle selection. Bayesian optimization is a global optimization technique which only needs to search a small fraction of the search space for slowly varying objective functions (i.e., smooth functions). Expedited constrained hierarchical optimization is run for some initial beam angle candidates and the resultant treatment plan for each beam configuration is rated using a clinically relevant treatment score function. Bayesian optimization iteratively predicts the treatment score for not-yet-evaluated candidates to find the best candidate to be optimized next with ECHO. We tested this technique on five head-and-neck (HN) patients with two coplanar beams. In addition, tests were performed with two noncoplanar and three coplanar beams for two patients. RESULTS: For the two coplanar configurations, the Bayesian optimization found the optimal beam configuration after running ECHO for, at most, 4% of all potential configurations (23 iterations) for all patients (range: 2%-4%). Compared with the beam configurations chosen by the planner, the optimal configurations reduced the mandible maximum dose by 6.6 Gy and high dose to the unspecified normal tissues by 3.8 Gy, on average. For the two noncoplanar and three coplanar beam configurations, the algorithm converged after 45 iterations (examining <1% of all potential configurations). CONCLUSIONS: A fully automated and efficient treatment planning process for proton therapy, including beam angle optimization was developed. The algorithm automatically generates high-quality plans with optimal beam angle configuration by combining Bayesian optimization and ECHO. As the Bayesian optimization is capable of handling complex nonconvex functions, the treatment score function which is used in the algorithm to evaluate the dose distribution corresponding to each beam configuration can contain any clinically relevant metric.


Assuntos
Terapia com Prótons , Radioterapia de Intensidade Modulada , Algoritmos , Teorema de Bayes , Humanos , Prótons , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
4.
J Ethnopharmacol ; 248: 112337, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31655148

RESUMO

ETHNOPHARMACOLIGICAL RELEVANCE: Paeonia lactiflora Pall. has long been used to treat inflammatory skin diseases, such as psoriasis. AIM OF THE STUDY: The skin acts as a barrier and provides protection against various stresses by expressing skin barrier genes during keratinocyte differentiation. However, the effect of Paeonia lactiflora Pall. root extract on the expression of skin barrier genes has not been investigated. Here, we aimed to show that treatment of keratinocytes with Paeonia lactiflora Pall. root can upregulate genes related to keratinocyte differentiation. MATERIALS AND METHODS: To determine the effect Paeonia lactiflora Pall. root extract, RNA-Seq, gene ontology, and gene set enrichment analysis were performed. Reverse transcriptase quantitative polymerase chain reaction analysis was performed to confirm the increased expression of skin barrier genes. RESULTS: Treatment with Paeonia lactiflora Pall. root enhanced the expression of skin barrier genes, including the filaggrin, loricrin, and involucrin. Moreover, we found that penta-O-galloyl-ß-D-glucose (PGG), one of the ingredients in Paeonia lactiflora Pall. root, enhanced the expression of skin barrier genes, by upregulating the expression of the transcription factor EGR3. CONCLUSIONS: PGG and Paeonia lactiflora Pall. root extract have therapeutic potential for the treatment of diseases related to skin barrier disruption and can be used in cosmetics to enhance skin barrier function.


Assuntos
Proteína 3 de Resposta de Crescimento Precoce/metabolismo , Prepúcio do Pênis/efeitos dos fármacos , Taninos Hidrolisáveis/farmacologia , Queratinócitos/efeitos dos fármacos , Paeonia , Extratos Vegetais/farmacologia , Raízes de Plantas , Proliferação de Células/efeitos dos fármacos , Proteína 3 de Resposta de Crescimento Precoce/genética , Proteínas Filagrinas , Prepúcio do Pênis/metabolismo , Regulação da Expressão Gênica , Humanos , Taninos Hidrolisáveis/isolamento & purificação , Queratinócitos/metabolismo , Masculino , Paeonia/química , Permeabilidade , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Transdução de Sinais
5.
Artigo em Inglês | MEDLINE | ID: mdl-24204389

RESUMO

Ampelopsis Radix, the root of Ampelopsis japonica (Thunb.) Makino (Vitaceae), is a herbal medicine which has been widely used in East Asia. The present study was done to explore whether the standardized extract of Ampelopsis Radix (AJW) protects dopaminergic neurons via antioxidant mechanisms in Parkinson's disease (PD) models. The effects of AJW on primary mesencephalic cultures stressed with 1-methyl-4-phenylpyridinium were investigated using tyrosine hydroxylase (TH) immunohistochemistry and reactive oxygen species measurement. The eliminative effects of AJW on the 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) radicals were explored using colorimetric methods. The effects of AJW on the mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were determined by pole test as well as TH and 8-hydroxydeoxyguanosine immunohistochemistry. AJW protected dopaminergic neurons by inhibiting reactive oxygen species generation in vitro. Moreover, AJW showed potent radical scavenging activities in vitro. In the mouse PD model, AJW protected the dopaminergic neurons in the brain, leading to motor improvements. AJW inhibited the MPTP-evoked accumulation of 8-hydroxydeoxyguanosine in the brain. These data suggest that AJW has neuroprotective effects with antioxidant mechanisms in PD models.

6.
Br J Nutr ; 104(1): 8-16, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20187987

RESUMO

Parkinson's disease (PD), one of the most common neurodegenerative disorders, is characterised by the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) to the striatum (ST), and involves oxidative stress. Mulberry fruit from Morus alba L. (Moraceae) is commonly eaten, and has long been used in traditional oriental medicine. It contains well-known antioxidant agents such as anthocyanins. The present study examined the protective effects of 70 % ethanol extract of mulberry fruit (ME) against neurotoxicity in in vitro and in vivo PD models. In SH-SY5Y cells stressed with 6-hydroxydopamine (6-OHDA), ME significantly protected the cells from neurotoxicity in a dose-dependent manner. Other assays demonstrated that the protective effect of ME was mediated by its antioxidant and anti-apoptotic effects, regulating reactive oxygen species and NO generation, Bcl-2 and Bax proteins, mitochondrial membrane depolarisation and caspase-3 activation. In mesencephalic primary cells stressed with 6-OHDA or 1-methyl-4-phenylpyridinium (MPP+), pre-treatment with ME also protected dopamine neurons, showing a wide range of effective concentrations in MPP+-induced toxicity. In the sub-acute mouse PD model induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), ME showed a preventative effect against PD-like symptoms (bradykinesia) in the behavioural test and prevented MPTP-induced dopaminergic neuronal damage in an immunocytochemical analysis of the SNpc and ST. These results indicate that ME has neuroprotective effects in in vitro and in vivo PD models, and that it may be useful in preventing or treating PD.


Assuntos
Antioxidantes/uso terapêutico , Encéfalo/efeitos dos fármacos , Dopamina/metabolismo , Intoxicação por MPTP/tratamento farmacológico , Morus , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Frutas , Humanos , Intoxicação por MPTP/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Neurotoxinas/farmacologia , Óxido Nítrico/biossíntese , Oxidopamina/farmacologia , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo
7.
J Ethnopharmacol ; 126(2): 361-5, 2009 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-19703534

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: While the hook of Uncaria rhynchophylla (URH) is a traditional herb used in northeast Asia for the treatment of Parkinson's disease (PD)-like symptoms such as tremor, it has not been experimentally evaluated in a PD model. AIM OF THE STUDY: We investigated the effects of URH on 6-hydroxydapamine (6-OHDA)-induced neurotoxicity in in vitro and in vivo models of PD. MATERIALS AND METHODS: The cell viability, anti-oxidative activity, and anti-apoptotic activity of a water extract of URH (URE) were assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide, reactive oxygen species (ROS), total glutathione (GSH), and caspase-3 assays in PC12 cells stressed by 6-OHDA. We also investigated the behavioral recovery and dopaminergic neuron protection of URE using an apomorphine-induced rotation test and tyrosine hydroxylase immunohistochemistry in the hemi-parkinsonian rat model of the unilateral 6-OHDA lesion of the medial forebrain bundle. RESULTS: In PC12 cells, URE significantly reduced cell death and the generation of ROS, increased GSH levels, and inhibited caspase-3 activity induced by 6-OHDA. In 6-OHDA-lesioned rats, posttreatment with URE (5 mg/kg/day for 14 days) significantly reduced apomorphine-induced rotation, and it lowered dopaminergic neuronal loss in substantia nigra pars compacta. CONCLUSIONS: URE possesses neuroprotective activity against 6-OHDA-induced toxicity through anti-oxidative and anti-apoptotic activities in PD models.


Assuntos
Antioxidantes/uso terapêutico , Apoptose/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Uncaria , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Caspase 3/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Glutationa/metabolismo , Masculino , Fármacos Neuroprotetores/farmacologia , Oxidopamina , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Fitoterapia , Estruturas Vegetais , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Substância Negra/efeitos dos fármacos
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